Research In Motion has turned down takeover overtures from Amazon.com and other potential buyers because the BlackBerry maker prefers to fix its problems on its own, according to people with knowledge of the situation. Amazon hired an investment bank this summer to review a potential merger with RIM, but it did not make a formal offer, said one of the sources. It is not clear whether informal discussions between Amazon and RIM ever led to specific price talk.

The Wall Street Journal reports that Microsoft and Nokia have discussed the idea of a joint bid for RIM, but the status of those talks remains unclear.

HSBC, Europe’s biggest bank, is retreating from Japan’s private banking market, selling a business that serves the wealthy to Credit Suisse, which is raising its profile in the world’s second-largest market for millionaires.

Tokio Marine said it will buy U.S. insurer Delphi Financial Group for $2.7 billion and is eying other acquisition targets, as Japan’s No.2 property-casualty insurer looks to expand outside its mature home market and diversify geographic risks.

Dozens of black-suited investigators, marching double-file, raided the office building of three small Olympus Corp subsidiaries Wednesday, one of 20 sites searched in a probe of a $1.7 billion accounting scandal that threatens the once-proud Japanese medical device maker’s survival.